314 lines
		
	
	
		
			9.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			314 lines
		
	
	
		
			9.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
 | |
| /*
 | |
|  * PCI Express Downstream Port Containment services driver
 | |
|  * Author: Keith Busch <keith.busch@intel.com>
 | |
|  *
 | |
|  * Copyright (C) 2016 Intel Corp.
 | |
|  */
 | |
| 
 | |
| #include <linux/aer.h>
 | |
| #include <linux/delay.h>
 | |
| #include <linux/interrupt.h>
 | |
| #include <linux/init.h>
 | |
| #include <linux/pci.h>
 | |
| 
 | |
| #include "portdrv.h"
 | |
| #include "../pci.h"
 | |
| 
 | |
| struct dpc_dev {
 | |
| 	struct pcie_device	*dev;
 | |
| 	u16			cap_pos;
 | |
| 	bool			rp_extensions;
 | |
| 	u8			rp_log_size;
 | |
| };
 | |
| 
 | |
| static const char * const rp_pio_error_string[] = {
 | |
| 	"Configuration Request received UR Completion",	 /* Bit Position 0  */
 | |
| 	"Configuration Request received CA Completion",	 /* Bit Position 1  */
 | |
| 	"Configuration Request Completion Timeout",	 /* Bit Position 2  */
 | |
| 	NULL,
 | |
| 	NULL,
 | |
| 	NULL,
 | |
| 	NULL,
 | |
| 	NULL,
 | |
| 	"I/O Request received UR Completion",		 /* Bit Position 8  */
 | |
| 	"I/O Request received CA Completion",		 /* Bit Position 9  */
 | |
| 	"I/O Request Completion Timeout",		 /* Bit Position 10 */
 | |
| 	NULL,
 | |
| 	NULL,
 | |
| 	NULL,
 | |
| 	NULL,
 | |
| 	NULL,
 | |
| 	"Memory Request received UR Completion",	 /* Bit Position 16 */
 | |
| 	"Memory Request received CA Completion",	 /* Bit Position 17 */
 | |
| 	"Memory Request Completion Timeout",		 /* Bit Position 18 */
 | |
| };
 | |
| 
 | |
| static int dpc_wait_rp_inactive(struct dpc_dev *dpc)
 | |
| {
 | |
| 	unsigned long timeout = jiffies + HZ;
 | |
| 	struct pci_dev *pdev = dpc->dev->port;
 | |
| 	struct device *dev = &dpc->dev->device;
 | |
| 	u16 cap = dpc->cap_pos, status;
 | |
| 
 | |
| 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 | |
| 	while (status & PCI_EXP_DPC_RP_BUSY &&
 | |
| 					!time_after(jiffies, timeout)) {
 | |
| 		msleep(10);
 | |
| 		pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 | |
| 	}
 | |
| 	if (status & PCI_EXP_DPC_RP_BUSY) {
 | |
| 		dev_warn(dev, "DPC root port still busy\n");
 | |
| 		return -EBUSY;
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev)
 | |
| {
 | |
| 	struct dpc_dev *dpc;
 | |
| 	struct pcie_device *pciedev;
 | |
| 	struct device *devdpc;
 | |
| 
 | |
| 	u16 cap;
 | |
| 
 | |
| 	/*
 | |
| 	 * DPC disables the Link automatically in hardware, so it has
 | |
| 	 * already been reset by the time we get here.
 | |
| 	 */
 | |
| 	devdpc = pcie_port_find_device(pdev, PCIE_PORT_SERVICE_DPC);
 | |
| 	pciedev = to_pcie_device(devdpc);
 | |
| 	dpc = get_service_data(pciedev);
 | |
| 	cap = dpc->cap_pos;
 | |
| 
 | |
| 	/*
 | |
| 	 * Wait until the Link is inactive, then clear DPC Trigger Status
 | |
| 	 * to allow the Port to leave DPC.
 | |
| 	 */
 | |
| 	pcie_wait_for_link(pdev, false);
 | |
| 
 | |
| 	if (dpc->rp_extensions && dpc_wait_rp_inactive(dpc))
 | |
| 		return PCI_ERS_RESULT_DISCONNECT;
 | |
| 
 | |
| 	pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS,
 | |
| 			      PCI_EXP_DPC_STATUS_TRIGGER);
 | |
| 
 | |
| 	return PCI_ERS_RESULT_RECOVERED;
 | |
| }
 | |
| 
 | |
| 
 | |
| static void dpc_process_rp_pio_error(struct dpc_dev *dpc)
 | |
| {
 | |
| 	struct device *dev = &dpc->dev->device;
 | |
| 	struct pci_dev *pdev = dpc->dev->port;
 | |
| 	u16 cap = dpc->cap_pos, dpc_status, first_error;
 | |
| 	u32 status, mask, sev, syserr, exc, dw0, dw1, dw2, dw3, log, prefix;
 | |
| 	int i;
 | |
| 
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS, &status);
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_MASK, &mask);
 | |
| 	dev_err(dev, "rp_pio_status: %#010x, rp_pio_mask: %#010x\n",
 | |
| 		status, mask);
 | |
| 
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_SEVERITY, &sev);
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_SYSERROR, &syserr);
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_EXCEPTION, &exc);
 | |
| 	dev_err(dev, "RP PIO severity=%#010x, syserror=%#010x, exception=%#010x\n",
 | |
| 		sev, syserr, exc);
 | |
| 
 | |
| 	/* Get First Error Pointer */
 | |
| 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &dpc_status);
 | |
| 	first_error = (dpc_status & 0x1f00) >> 8;
 | |
| 
 | |
| 	for (i = 0; i < ARRAY_SIZE(rp_pio_error_string); i++) {
 | |
| 		if ((status & ~mask) & (1 << i))
 | |
| 			dev_err(dev, "[%2d] %s%s\n", i, rp_pio_error_string[i],
 | |
| 				first_error == i ? " (First)" : "");
 | |
| 	}
 | |
| 
 | |
| 	if (dpc->rp_log_size < 4)
 | |
| 		goto clear_status;
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG,
 | |
| 			      &dw0);
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 4,
 | |
| 			      &dw1);
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 8,
 | |
| 			      &dw2);
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 12,
 | |
| 			      &dw3);
 | |
| 	dev_err(dev, "TLP Header: %#010x %#010x %#010x %#010x\n",
 | |
| 		dw0, dw1, dw2, dw3);
 | |
| 
 | |
| 	if (dpc->rp_log_size < 5)
 | |
| 		goto clear_status;
 | |
| 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_IMPSPEC_LOG, &log);
 | |
| 	dev_err(dev, "RP PIO ImpSpec Log %#010x\n", log);
 | |
| 
 | |
| 	for (i = 0; i < dpc->rp_log_size - 5; i++) {
 | |
| 		pci_read_config_dword(pdev,
 | |
| 			cap + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG, &prefix);
 | |
| 		dev_err(dev, "TLP Prefix Header: dw%d, %#010x\n", i, prefix);
 | |
| 	}
 | |
|  clear_status:
 | |
| 	pci_write_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS, status);
 | |
| }
 | |
| 
 | |
| static int dpc_get_aer_uncorrect_severity(struct pci_dev *dev,
 | |
| 					  struct aer_err_info *info)
 | |
| {
 | |
| 	int pos = dev->aer_cap;
 | |
| 	u32 status, mask, sev;
 | |
| 
 | |
| 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
 | |
| 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, &mask);
 | |
| 	status &= ~mask;
 | |
| 	if (!status)
 | |
| 		return 0;
 | |
| 
 | |
| 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &sev);
 | |
| 	status &= sev;
 | |
| 	if (status)
 | |
| 		info->severity = AER_FATAL;
 | |
| 	else
 | |
| 		info->severity = AER_NONFATAL;
 | |
| 
 | |
| 	return 1;
 | |
| }
 | |
| 
 | |
| static irqreturn_t dpc_handler(int irq, void *context)
 | |
| {
 | |
| 	struct aer_err_info info;
 | |
| 	struct dpc_dev *dpc = context;
 | |
| 	struct pci_dev *pdev = dpc->dev->port;
 | |
| 	struct device *dev = &dpc->dev->device;
 | |
| 	u16 cap = dpc->cap_pos, status, source, reason, ext_reason;
 | |
| 
 | |
| 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 | |
| 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_SOURCE_ID, &source);
 | |
| 
 | |
| 	dev_info(dev, "DPC containment event, status:%#06x source:%#06x\n",
 | |
| 		 status, source);
 | |
| 
 | |
| 	reason = (status & PCI_EXP_DPC_STATUS_TRIGGER_RSN) >> 1;
 | |
| 	ext_reason = (status & PCI_EXP_DPC_STATUS_TRIGGER_RSN_EXT) >> 5;
 | |
| 	dev_warn(dev, "DPC %s detected, remove downstream devices\n",
 | |
| 		 (reason == 0) ? "unmasked uncorrectable error" :
 | |
| 		 (reason == 1) ? "ERR_NONFATAL" :
 | |
| 		 (reason == 2) ? "ERR_FATAL" :
 | |
| 		 (ext_reason == 0) ? "RP PIO error" :
 | |
| 		 (ext_reason == 1) ? "software trigger" :
 | |
| 				     "reserved error");
 | |
| 
 | |
| 	/* show RP PIO error detail information */
 | |
| 	if (dpc->rp_extensions && reason == 3 && ext_reason == 0)
 | |
| 		dpc_process_rp_pio_error(dpc);
 | |
| 	else if (reason == 0 &&
 | |
| 		 dpc_get_aer_uncorrect_severity(pdev, &info) &&
 | |
| 		 aer_get_device_error_info(pdev, &info)) {
 | |
| 		aer_print_error(pdev, &info);
 | |
| 		pci_cleanup_aer_uncorrect_error_status(pdev);
 | |
| 		pci_aer_clear_fatal_status(pdev);
 | |
| 	}
 | |
| 
 | |
| 	/* We configure DPC so it only triggers on ERR_FATAL */
 | |
| 	pcie_do_fatal_recovery(pdev, PCIE_PORT_SERVICE_DPC);
 | |
| 
 | |
| 	return IRQ_HANDLED;
 | |
| }
 | |
| 
 | |
| static irqreturn_t dpc_irq(int irq, void *context)
 | |
| {
 | |
| 	struct dpc_dev *dpc = (struct dpc_dev *)context;
 | |
| 	struct pci_dev *pdev = dpc->dev->port;
 | |
| 	u16 cap = dpc->cap_pos, status;
 | |
| 
 | |
| 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 | |
| 
 | |
| 	if (!(status & PCI_EXP_DPC_STATUS_INTERRUPT) || status == (u16)(~0))
 | |
| 		return IRQ_NONE;
 | |
| 
 | |
| 	pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS,
 | |
| 			      PCI_EXP_DPC_STATUS_INTERRUPT);
 | |
| 	if (status & PCI_EXP_DPC_STATUS_TRIGGER)
 | |
| 		return IRQ_WAKE_THREAD;
 | |
| 	return IRQ_HANDLED;
 | |
| }
 | |
| 
 | |
| #define FLAG(x, y) (((x) & (y)) ? '+' : '-')
 | |
| static int dpc_probe(struct pcie_device *dev)
 | |
| {
 | |
| 	struct dpc_dev *dpc;
 | |
| 	struct pci_dev *pdev = dev->port;
 | |
| 	struct device *device = &dev->device;
 | |
| 	int status;
 | |
| 	u16 ctl, cap;
 | |
| 
 | |
| 	if (pcie_aer_get_firmware_first(pdev))
 | |
| 		return -ENOTSUPP;
 | |
| 
 | |
| 	dpc = devm_kzalloc(device, sizeof(*dpc), GFP_KERNEL);
 | |
| 	if (!dpc)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	dpc->cap_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC);
 | |
| 	dpc->dev = dev;
 | |
| 	set_service_data(dev, dpc);
 | |
| 
 | |
| 	status = devm_request_threaded_irq(device, dev->irq, dpc_irq,
 | |
| 					   dpc_handler, IRQF_SHARED,
 | |
| 					   "pcie-dpc", dpc);
 | |
| 	if (status) {
 | |
| 		dev_warn(device, "request IRQ%d failed: %d\n", dev->irq,
 | |
| 			 status);
 | |
| 		return status;
 | |
| 	}
 | |
| 
 | |
| 	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CAP, &cap);
 | |
| 	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl);
 | |
| 
 | |
| 	dpc->rp_extensions = (cap & PCI_EXP_DPC_CAP_RP_EXT);
 | |
| 	if (dpc->rp_extensions) {
 | |
| 		dpc->rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
 | |
| 		if (dpc->rp_log_size < 4 || dpc->rp_log_size > 9) {
 | |
| 			dev_err(device, "RP PIO log size %u is invalid\n",
 | |
| 				dpc->rp_log_size);
 | |
| 			dpc->rp_log_size = 0;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	ctl = (ctl & 0xfff4) | PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN;
 | |
| 	pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl);
 | |
| 
 | |
| 	dev_info(device, "DPC error containment capabilities: Int Msg #%d, RPExt%c PoisonedTLP%c SwTrigger%c RP PIO Log %d, DL_ActiveErr%c\n",
 | |
| 		cap & PCI_EXP_DPC_IRQ, FLAG(cap, PCI_EXP_DPC_CAP_RP_EXT),
 | |
| 		FLAG(cap, PCI_EXP_DPC_CAP_POISONED_TLP),
 | |
| 		FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), dpc->rp_log_size,
 | |
| 		FLAG(cap, PCI_EXP_DPC_CAP_DL_ACTIVE));
 | |
| 	return status;
 | |
| }
 | |
| 
 | |
| static void dpc_remove(struct pcie_device *dev)
 | |
| {
 | |
| 	struct dpc_dev *dpc = get_service_data(dev);
 | |
| 	struct pci_dev *pdev = dev->port;
 | |
| 	u16 ctl;
 | |
| 
 | |
| 	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl);
 | |
| 	ctl &= ~(PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN);
 | |
| 	pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl);
 | |
| }
 | |
| 
 | |
| static struct pcie_port_service_driver dpcdriver = {
 | |
| 	.name		= "dpc",
 | |
| 	.port_type	= PCIE_ANY_PORT,
 | |
| 	.service	= PCIE_PORT_SERVICE_DPC,
 | |
| 	.probe		= dpc_probe,
 | |
| 	.remove		= dpc_remove,
 | |
| 	.reset_link	= dpc_reset_link,
 | |
| };
 | |
| 
 | |
| int __init pcie_dpc_init(void)
 | |
| {
 | |
| 	return pcie_port_service_register(&dpcdriver);
 | |
| }
 | 
